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A198239 Decimal expansion of greatest x having 3*x^2+4x=2*cos(x). 3

%I #5 Mar 30 2012 18:57:54

%S 3,6,6,2,4,0,8,1,5,6,6,0,4,6,3,7,1,8,3,8,4,1,5,8,1,8,8,6,9,7,6,4,4,4,

%T 0,5,4,7,4,3,1,6,0,8,8,4,0,0,7,0,5,9,1,1,9,3,7,7,4,4,5,1,4,1,3,6,4,9,

%U 0,2,2,0,6,8,1,8,3,5,2,1,5,9,0,0,0,7,9,7,9,3,0,3,4,1,8,4,5,4,4

%N Decimal expansion of greatest x having 3*x^2+4x=2*cos(x).

%C See A197737 for a guide to related sequences. The Mathematica program includes a graph.

%e least x: -1.40936392163577784477286936880153979511...

%e greatest x: 0.36624081566046371838415818869764440...

%t a = 3; b = 4; c = 2;

%t f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]

%t Plot[{f[x], g[x]}, {x, -2, 1}]

%t r1 = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.4}, WorkingPrecision -> 110]

%t RealDigits[r1](* A198238 *)

%t r2 = x /. FindRoot[f[x] == g[x], {x, .36, .37}, WorkingPrecision -> 110]

%t RealDigits[r2](* A198239 *)

%Y Cf. A197737.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Oct 23 2011

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Last modified August 21 22:52 EDT 2024. Contains 375353 sequences. (Running on oeis4.)